Past, future, and fantasy climate change - from the mid-Cretaceous to Middle Earth

As a curiosity-driven scientist, understanding the past climate of our Earth (from the scorching greenhouse of the mid-Cretaceous, to the frozen wastes of the last ice age) is of fundamental interest. However, to what extent can such understanding improve our predictions of future climate change? And what can we learn about climate from the Lord of the Rings?!